Castrol GTX 5w30, 9750 miles OCI, 2000 Mustang 3.8

Status
Not open for further replies.
Originally Posted By: ARCOgraphite
Originally Posted By: webfors
Originally Posted By: Dave_Reagan
I think I am going to run Walmart Supertech next change and go 10k just to irritate some people on here. :


LOL.gif


run what you like, for as long as you like. It's not my car so I really don't care what you do with it. If pushing the limits turns your crank, stick with it. But be clear, it makes no difference to 99% of people on this board what you do with your stang.
Not very polite, Web.

Dave:There are many STS fans here doing excellent,long OCI on STS. This is a big club. I'm not in it, but its a big fanbase.


Hey, he started it!!
grin2.gif


My point is, it's pretty silly motivation. Do what's best for you and your car. Why do you care what other people think...?

Ok, I admit, I'm a little off tonight. Buddies are dropping out of our Kayak expedition to Georgian Bay and I'm not as happy as I usually am.. sorry if I'm offending anyone.
 
Originally Posted By: daman
Originally Posted By: Bill in Utah
Originally Posted By: daman
Mmmmm Kool-Aid......U R my idle
smirk2.gif



It's idol BTW...

No..i ment idle??


Knowing you and your mindset, you prob did...
smirk2.gif


And it's meant...
LOL.gif
 
Originally Posted By: webfors

Honda Canada states 5k mile oci. Subaru Canada mandates a 3750 mile oci. Honda's I4 and Subaru's H4 are two of the easiest engines on oil. General statements can be the root of all evil.
smirk2.gif


Is the OCI from Subaru NOT 7,500 miles or 6 months?

My US 2007 is. The turbos are the 3,750mi OCI...

Bill
 
Most, if not all conventional oils are good for about 7,500 miles and will keep the engine clean. API SM oils are using Group II+ and III base oils. Times have changed.
 
Originally Posted By: Bill in Utah
Originally Posted By: webfors

Honda Canada states 5k mile oci. Subaru Canada mandates a 3750 mile oci. Honda's I4 and Subaru's H4 are two of the easiest engines on oil. General statements can be the root of all evil.
smirk2.gif


Is the OCI from Subaru NOT 7,500 miles or 6 months?

My US 2007 is. The turbos are the 3,750mi OCI...

Bill


Not in Canada. 3750 (6k km) across the board for everyone.
 
Originally Posted By: webfors
Originally Posted By: Bill in Utah
Originally Posted By: webfors

Honda Canada states 5k mile oci. Subaru Canada mandates a 3750 mile oci. Honda's I4 and Subaru's H4 are two of the easiest engines on oil. General statements can be the root of all evil.
smirk2.gif


Is the OCI from Subaru NOT 7,500 miles or 6 months?

My US 2007 is. The turbos are the 3,750mi OCI...

Bill


Not in Canada. 3750 (6k km) across the board for everyone.


What is the factory recommended OCI up there for syn oil?
 
you guys are funny
10.gif


Originally Posted By: ARCOgraphite
Originally Posted By: daman
Originally Posted By: Bill in Utah
Originally Posted By: daman
Mmmmm Kool-Aid......U R my idle
smirk2.gif



It's idol BTW...

No..i ment idle??


It's Meant BTW...
 
I think this is a very good UOA. Insolubles at 0.3... what's not to like? 33 parts per MILLION of iron in the elemental is nothing huge either for a 100K engine... especially with an old tech kinda engine like the 3.8L. The TBN was 2.7 on a 7100 mile interval and check out how well the flashpoint held out on both tests. No worries here at all.

What filter you runnin', Dave? An upgrade there might improve the next test a bit on the wear metal numbers.
 
Originally Posted By: ARCOgraphite
Originally Posted By: Pablo
Originally Posted By: ARCOgraphite
run a killer oil filter (m1, Pureone, Fram extended guard, Bosch w/ filtech) and see if we cant get that FE down to trace. A grp-iii base oil would be better than a PAO for that.


Pure speculation and guessing is not what BITOG is all about.

So first we will need the data that those oil filters will lower Fe , then we will be waiting for the data that shows a group III base oil produces lower Fe in UOA's than Group IV based oils.
Speculation? The "better" filter media will keep the Fe suspension out of the analysis sample, And these brands have already been shown to improve particulate counts in some of our members studies. Just regurgitating what I've read here. Granted the Fe may be solubilised through EP AW action and may be difficult to minimise. I dont think its speculation that PAO is a substandard lubricant in the EP and boundary lubrication regime. So he should try nothing different? Nothing Ventured? Nothing to be done to move the understanding process forward at his expense providing our entertainment?!


OK let's step back and digest this for a moment. I'll take it line by line - just to get to root of this.

Quote:
The "better" filter media will keep the Fe suspension out of the analysis sample


While it is empirically true that the finer media SHOULD "catch" more particulate matter, there is not necessarily a correlation between "better" brands and finer media. Nor is there a direct correlation between dissolved metals in a UOA and the brand of filter.

Quote:
And these brands have already been shown to improve particulate counts in some of our members studies.


This is not true. And if you think it's true please post the data for the brands you mention. And again see my first point. You changed from ppm of dissolved metals to particulate counts (although it turns out some labs really infer particulate counts)

Quote:
. Just regurgitating what I've read here.


Well you are selectively regurgitating. Not picking on you, we all do it to some degree. It just should not be passed on as unbiased truth.

Quote:
Granted the Fe may be solubilised through EP AW action and may be difficult to minimise


Now we are getting somewhere. We don't really know where the Fe came from, and yes some is put in solution via kelation with some AW and other additive chemicals. If we understand something we can seek to control the important parts of it.

Quote:
I dont think its speculation that PAO is a substandard lubricant in the EP and boundary lubrication regime.


Seems you have read some of those statements. While there is some truth about some pure PAO's, this is just not that difficult of a problem to overcome. Also the way the statements are written, they always seem a bit of an overstatement. "Hopeless boundary lubricant….." is the one I often see. That is utter garbage. Most well compounded PAO base oils have at least 3 levels built in for increasing boundary lubrication. Selecting the correct PAO's, using the correct surfactants, using esters or other polar base oil components, and using other additives (such as stable amines), along with new age AW additives as some of the best AW/EP protectants (that's five!). BUT let's get back to your original statement….

Quote:
- "A grp-iii base oil would be better than a PAO for that."


And, sir it's simply not true. You have provided no proof. Only regurgitation. I have nothing against Group III oils!! But when people make such seemingly factual statements, proof must be provided. You didn't write "may" or "could". You wrote that statement as fact.

Quote:
So he should try nothing different? Nothing Ventured? Nothing to be done to move the understanding process forward at his expense providing our entertainment?!

I don't necessarily think he should change oils right away. And yes, we all should understand the process.
 
I would be hard pressed to run many Syn oils this long.

Remember most "Major" syn oils don't claim to be long OCI oils.
 
It seems you agreed with me on most every point. Sorry about the "broad" ststements on PAO v Grp-iii; Motor oil is a complete synergistic package formulation and it is broken and inadequate missing any key component. That said, If I had to take a pure base oil and use it on my motorcycle to escape blood crazed zombies, I might prefer a grp-1 or -ii oil over a pure unadditised PAO. Then again, I havent seen any engine tests with unadditised oils, so my statements are based on general knowledge of the comparitive properties of the two.
 
I don't understand why people are on a board that talks about used oil analysis who throw the results out and "play it safe" even when us who go long OCI's are getting good results. Isn't the point of this to be scientific about changing oil when it's needed, not when we think it might be needed? Here's a little equation I just ran for fun. The bore and stroke of my engine are 3.811 and 3.86" respectively. So bore circumference is 3.14*3.811= 11.966 inches. Circumference X Stroke X 6 cylinders = total swept bore area. 11.966*3.86*6= 277 square inches. I only got 4 quarts of oil when I drained it, so it's a perfect gallon. There are 231 cubic inches in a gallon. At 33ppm of iron, that makes .000033*231= .007623 cubic inches of iron. At 10,000 mile OCI, that would mean 15 oil changes to make 150k, so we'd have an iron yield of .007623*15= .1143 cubic inches of iron. Divide the .1143 cubic inches of iron by the bore area of 277 square inches and we have .00041" on each side of the wall if the wear were perfectly even. This actually came out higher than I thought it would. I realize this is an incomplete equation but it's a start. This does not consider any iron coming from the valve train or the crank, so it's kind of a worst case for the cylinder bores, but I do think the bore area is much larger than all the valvetrain and crank put together. Also, those surfaces are hardened, and the bores are not. Are there any engine builders on here who would like to weigh in?
 
Thanks Dave. Your formula does a good job of allowing us to visualize just how little the accumulated wear truly is. Now when I see a high Fe count, It'll be a lot less alarming.

I wish people could just be honest with themselves and admit that they change oil prematurely because they want to (for a variety of gratifications), not because their engine survival depends on it.

I change my oil more often than I need to and propbably always will. I enjoy taking good care of my car so that is how I justify it. My wife just assumes that cars require that much maintenance ;-)
 
Originally Posted By: Dave_Reagan
Are there any engine builders on here who would like to weigh in?
Dave, I like your calc! The only issue may be the majority wear will be at the top 1/2" of the stroke and possibly biased to the pin offset, next the bottom of the stroke. the Middle 70% of swept area should be wear free given no stuck rings. You'll get some Fe off the cams, less with a roller, and rocker pivots, and the minimal "sandblasting" effect of the cranckcase oil fog on the rods and crank. Crank thrust flange wear will be all soft metals.
HTH. -Grumpy
 
Last edited:
Status
Not open for further replies.
Back
Top